Different training instructions in persons with rheumatic and musculoskeletal diseases.

Introduction: People with rheumatic and musculoskeletal diseases are advised to do aerobic exercise for symptom relief and to reduce the risk of cardiovascular disease. Continuous exercise at an intensity causing a rate of perceived exertion of 15, on a 6-20-point Borg scale, exemplifies such exercise. Also, the instruction "Now you need to increase your heart rate" is used before aerobic exercise. However, the exercise intensity caused by that instruction is unknown. We tested the hypothesis that intensity during cycling, initiated with the instruction "Now you need to increase your heart rate", is lower than when targeting a Borg scale score of 15.

Methods: Participants (n = 15) with various types of rheumatic and musculoskeletal diseases cycled at a self-selected power output. Subsequently, we determined the relationship between Borg scale score and exercise intensity (heart rate and power output), including intensity at a target score of 15. Additionally, intensity was measured during 20 minutes of cycling exercise executed after the instruction "Now you need…".

Results: Power output and percentage of maximal heart rate were 89 (± 40) W and 86% (± 9%), respectively, at a Borg scale score of 15, whereas values were 81 (± 33) W and 81% (± 7%) during the instructed cycling exercise (p less-than 0.05).

Conclusions: Intensity, in the form of power output and percentage of maximal heart rate, during cycling exercise, initiated with the instruction "Now you need to increase your heart rate", was 8 W and 5 percentage points lower, respectively, than during cycling targeting a Borg scale score of 15.

Funding: None.

Trial registration: Not relevant.